The invention relates to circular knitting machines, especially machines for manufacturing hosiery or the like, that are provided with latch needles mounted in a needle cylinder. In operation, the needles are lowered and lifted by means of swinging sinkers which are provided with two guiding butts alternately engageable with cam channels. Alternatively, the butts can be provided immediately on the needles, or on guiding sinkers of double-head needles.
Circular knitting machines provided with swinging sinkers having two guiding butts are well known. These machines are adapted for reverse knitting operations, such as knitting heels and toes of hosiery, and particularly in a single feed system. The system is usually provided with a right and left sinking cam as well as with heel cam which is designed for displacing the needles onto the level of the sinking cams, i.e. in both knitting directions. Due to such an arrangement, the cam channels for the butts of the needles or for the needle guiding sinkers cross each other. Below the heel cam there is provided a compensating cam which is designed for positioning the needles and for preventing the needles form assuming, owing to the knitting speed, a position which is lower than the position which is necessary for laying thread into the needles. Consequently, the needle races are broken, and the guiding butts are exposed to many shocks which causes paths to lose their curvilinear course. The motion, especially with double-cylinder machines, is ensured within a section, by the lower butts of the guiding sinkers so that even the race continuity is impaired. Therefore, any increase in knitting speed is difficult.